1. Field of the Invention
The invention relates to a plate-type heat exchanger having a plate block or a stack of partition plates, which delimit flow channel layers between them. In other words, the partition plates serve as fluid-separating walls between successive flow channel layers in the stack direction. These successive flow channel layers usually comprise two or more different liquid or gaseous heat transfer media which are to be brought into thermal contact with one another. The heat transfer media usually flows through the channels in an alternating manner. The partition plates, preferably, have a good thermal conductivity.
2. Description of Related Art
A plate-type heat exchanger is described in commonly assigned, earlier German patent application 199 09 881. The crosscurrent-type heat exchanger described therein includes partition plates, into which shaped-out moldings are formed. Regions of the partition plates in the plate block are in contact with adjacent partition plates by means of the shaped-out moldings. In each instance, adjacent partition plates are spaced apart by the shaped-out molding regions and thereby form the boundaries for a flow channel layer, in the stack direction, between the partition plates. In side regions, the partition plates are provided with inlet-channel and outlet-channel apertures. Through the aligned overlap of these apertures on the edge side of the stack, manifold channels which open out at the end sides of the stack are formed. These manifold channels serve the purpose of distributing the respective heat-transfer medium to the corresponding flow channel layers and for collecting the heat-transfer medium which leaves the flow channel layers.
The documents DE 197 07 648 A1 and DE 198 15 218 A1 have described plate-type heat exchangers. The stacked structure of these heat exchangers includes flat plates of different types. Specifically, these flow channel plates include plates which are provided with apertures which form flow channels, as well as partitioning intermediate plates which are arranged alternately with the flow channel plates in the stack and serve as partitions for the flow channels of the flow channel plates. Depending on the particular embodiment, lateral manifold apertures which overlap one another in an aligned manner in the stack are made in all the plates. This forms corresponding manifold channels which open out at the end sides of the stack. Alternatively, the flow channels of the flow channel plates, in both end regions, extend beyond the intermediate or partition plates. As a result, a connection structure is formed, in which the relevant heat-transfer medium can be fed laterally to the stack and removed therefrom. In the process, on the relevant stack sides of the intermediate plate planes, the heat transfer medium passes into the protruding flow channels of the flow channels plates and, in a corresponding manner, passes out of them again.